and the bisect2.m function, I calculated the following four smallest roots for f ( x ) f(x), [ 3.07645 , 3.19925 ] [3.07645,3.19925] using the brackets, [ 3 , ] [3,] and [ , 4 ] [,4] respectively. The next two roots turned out to be, [ 9.42395 , 9.42590 ] [9.42395,9.42590] with brackets [ 9 , 3 ] [9,3] and [ 3 , 10 ] [3,10] respectively. As seen the roots get closer and closer together as x x increases, because the fraction, 1 1 + e 2 x 1+e 2x 1 approaches 1, making it equal to f + ( x ) f + (x) when x x is large, in other words the f ( x ) f(x) graph on the positive side ... [text obscured] ... at each x x." Boxed note on the right (overlayed): "(d) Must find the four smallest positive roots of f ( x ) f(x)